EP2136098A1 - Synchronising ring and a cog-wheel gearbox for a motor vehicle - Google Patents

Abstract

The ring (1) has a locking device (11) i.e. safety lug, provided for fixing the ring in an installation condition in a cylindrical hollow chamber of a synchronous ring hub. The locking device is integrally connected with a ring body (3) and extends in a direction from a toothed wheel surface (7) of the ring body. A guide element (12) is provided for guiding an outer installation surface (5) into the hollow chamber at the locking device. The body is limited in an axial direction in a larger cone dimension through the toothed wheel surface, which runs perpendicular to a synchronous axle (6).

Description

The invention relates to a synchronizer ring for a synchronizer of a shiftable change-speed gearbox and a change-speed gearbox for a vehicle according to the preamble of independent claims 1 and 13.

Synchronizer rings serve in a mechanical shiftable change-speed gearbox, e.g. in vehicle transmissions to match the occurring during a gear change relative speeds between gear and gear shaft to each other. The synchronization is achieved by friction between the corresponding friction partner. The mode of operation of such transmissions and the course of the synchronization process are known per se and need not be explained in more detail to the person skilled in the art.

To protect against premature wear and / or to improve the friction characteristic, it is known to provide the friction surfaces of synchronizer rings, which are usually made of a metal or a metal alloy, such as brass or steel, with a friction layer. there are very different types of friction layers in use, eg thermal spray coatings of molybdenum, carbon friction layers or friction layers of other materials.

In the DE 35 19811 A1 a carrier for a cone-shaped synchronizer ring is described, which has a three-divided outer ring gear and in a cylindrical cavity of a Synchronringnabe, which is often referred to as a synchronizer ring body is arranged and via stops, which are formed as lobes with the synchronizer ring hub substantially rotationally fixed is anchored. Substantially non-rotatable means in the context of this application that, except for small angular deflections in the circumferential direction of the synchronizer ring is rotatably connected to the synchronizer ring hub.

The DE 198 53 856 A1 describes a development of the above-described synchronizer ring, wherein the synchronizer ring of DE 198 53 856 A1 characterized in that its width is determined substantially only by the required width of its friction surface. This is achieved by making a stop that functionally matches the cloth DE 35 19811 A1 correspond to, is arranged on or near an end portion of the annular body with a smaller cone diameter, and the contour of the stop protrudes in the radial direction over the contour of the outer circumferential surface of the annular body.

Although both synchronizer rings are well secured in the operating state against rotation relative to the Synchronringnabe by the lobes or attacks in principle, but both lack a reliable guide in the radial direction in the cylindrical cavity in the synchronizer hub.

That is, against a rotation in the circumferential direction with respect to the synchronizer hub are known from the prior art Although synchronizer rings secured, however, these rings tend due to their conical outer shape, which cooperates with a cylindrical inner contact surface in the cylindrical cavity of Synchronringnabe, reinforced uncontrolled movements, eg too small radial deflections or tilting movements, which can be expressed in unpleasant vibrations, so the reliability and accuracy of the synchronization process adversely affect, which can lead to an increase in switching times, leads to faster and increased wear of the friction surface and the entire synchronizer ring as such, and thus leads to shorter repair and maintenance intervals, quite apart from that poor guidance of the synchronizer ring in the cavity of the synchronizer ring hub and the resulting uncontrolled movements of the switching and driving comfort of a motor vehicle is significantly limited. These effects become more significant, the more power or torque must be switched by a corresponding gear.

In fact, the problem with synchronizer rings made from formed steel sheets is that it is not possible to form a cylindrical outside because a conical friction surface has to be created during forming. So far, more or less successful attempts have been made to defuse this problem. For example, attempts have been made to improve the guidance of the synchronizing ring in the cylindrical cavity of the synchronizing ring hub by adapting the conical outer side of the friction surface to the cylindrical shape of the synchronizing ring hub by thickening or by bending additional straps. However, these known solutions have some significant disadvantages, e.g. what concerns the production but above all the rigidity of the synchronizer ring.

A significant improvement was therefore by the applicant already with the EP 1 900 955 A1 proposed.

This invention relates to a synchronizer ring for a synchronizer of a shiftable change-speed gearbox, wherein for securing the synchronizer ring in a cylindrical cavity of a Synchronringnabe an anti-rotation is provided, which is integrally connected to the annular body and extending from the gear surface of the annular body in the direction of the hub surface. To guide the mounting surface in the cavity of the synchronizer hub, a guide element is provided on the annular body in a predeterminable area between the gear surface and the hub surface.

It is essential for this invention that a guide element is provided for supporting or centering and guiding the installation surface on an inner surface of the cylindrical cavity of the synchronizing ring hub on the annular body in a predeterminable area between the gear surface and the hub surface, preferably in the form of several bulges, which are distributed over the mounting surface in the circumferential direction, is provided.

For explanation, see Fig. 1 a simple embodiment of the from EP 1 900 955 known synchronizer ring shown schematically. Fig. 2 shows the synchronizer ring the Fig. 1 in the installed state.

For better distinction of the present invention from the prior art are in the Fig. 1 and Fig. 2 which show the prior art, the reference numerals with a single quote, while the reference numerals of Fig. 3 to Fig. 7 , the embodiments of the invention show, do not wear apostrophes.

The well-known synchronizer ring 1 'of Fig. 1 comprises a conical annular body 3 'with an inner friction surface 4' with carbon friction lining 41 'and an outer mounting surface 5', the annular body 3 'in a radial Limit the circumferential direction in each case. The outer mounting surface 5 'and the inner friction surface 4' extend substantially parallel to each other at a predeterminable friction angle α∋, the in Fig. 1 can not be seen, conical about an axial synchronizer ring axis 6 'of the synchronizer ring 1'.

In this case, the annular body 3 'in the axial direction at a maximum cone diameter d1' by a substantially perpendicular to the synchronizer ring axis 6 'extending gear surface 7' with gear 71 'limited, and limited to a smallest cone diameter d2' by a hub surface 8 '. For fixing the synchronizer ring 1 'in a cylindrical cavity 9' of a synchronizer ring hub 10 ', which in Fig. 1 is not shown, a rotation 11 'is provided, which is integrally connected to the annular body 3' and extends from the gear surface 7 'of the annular body 3' in the direction of the hub surface 8 ', a construction as in principle from the prior Technology has long been known. In this case, the rotation 11 'according to Fig. 1 a securing tab 111 ', which may be formed in the direction of the mounting surface 5', for example, in the manufacture of the synchronizer ring 1 'by bending over a portion of the annular body 3' initially radially outwardly.

That is, the rotation 11 ', which is designed as a securing tab 111', extends on the synchronous ring axis 6 'side facing away from the annular body 3' substantially rectified to the mounting surface 5 '.

The securing tab 111 'is designed and arranged with respect to the installation surface 5' such that the securing tab 111 'in the installed state can be anchored in a corresponding recess 101' of the synchronizing ring hub 10 '.

To guide the mounting surface 5 'on an inner surface 91' of the cylindrical cavity 9 'of the synchronizing ring hub 10' is on the annular body 3 'in one predeterminable area between the gear surface 7 'and the hub surface 8', a guide member 12 'is provided, which is in the form of a bulge 12' of the annular body 3 'on the mounting surface 5' is formed, wherein the bulge 12 'of the synchronizer ring axis 6' radially away extends to the outside.

That is an essential feature of the known synchronizer ring 1 'according to EP 1 900 955 A1 can be seen that the guide element 12 'is provided directly on the ring body 3' even in the form of a bulge 12 ', that is, the formation of the guide member 12' affects or alters at least the geometry, but possibly also mechanical properties such as stiffness and strength of the known synchronizer ring 1 '.

In the installed state of the synchronizer ring 1 ', the bulges 12' center and guide the synchronizer ring 1 'safely and reliably in the cylindrical cavity 9' provided in the synchronizer ring hub 10 'for receiving the mounting surface 5'.

For a better understanding of the interaction between synchronizer ring 1 'and synchronizer ring hub 10' is in Fig. 2 a side view of a synchronizer ring 1 'according to Fig. 1 shown schematically in the installed state. The section is along the arrow A according to Fig. 3 just chosen so that the securing tab 111 'is not visible.

The conical annular body 3 'with its inner friction surface 4', in the present example a carbon friction lining 41 ', and the outer mounting surface 5', extend at the friction angle α∋ conical and substantially parallel to each other about the axial synchronizer ring axis 6 ' of the synchronizer ring 1 '.

The synchronizer ring 1 'is centered by the guide elements 12', which are provided as bulges 12 ', with the mounting surface 5' in the cavity 9 'of the synchronizer ring hub 10'.

The gear surface 7 'with gear 71' is located outside the synchronizer ring hub 10 ', so that the gear 71' with another, in Fig. 2 not shown gear of a switchable change-speed transmission also not shown in rotationally fixed engagement can occur.

Although the synchronizer ring according EP 1 900 955 Although the problems previously known from the prior art solves outstanding, there is still a certain need for improvement. Although the synchronizer ring according to EP 1 900 955 Excellent running properties in the operating state and is performed extremely stable in the operating state in the synchronizer hub.

However, the bulges that are distributed over the installation surfaces, of course, to the detriment of the friction surface.

The object of the invention is therefore to provide an improved synchronizer ring, which is optimally guided in the synchronizer ring hub, so that in the operating state no uncontrolled relative movements between synchronizer ring and Synchronringnabe occur during and / or outside the synchronization process. At the same time the conical friction surface should not be changed by bulges, thickenings or the like. In addition, a correspondingly improved change-speed gearbox is to be made available.

The objects of the invention solving these objects are characterized by the features of independent claims 1 and 13.

The dependent claims relate to particularly advantageous embodiments of the invention.

The invention thus relates to a synchronizer ring for a synchronizer of a change-speed gearbox, comprising a conical annular body having an inner friction surface and an outer mounting surface, each defining the annular body in a radial circumferential direction which is perpendicular to an axial synchronizer ring axis, and at a predeterminable friction angle extend conically around the axial synchronizer ring axis of the synchronizer ring. In this case, the annular body is limited in the axial direction at a maximum cone diameter by a substantially perpendicular to the synchronizer ring axis extending gear surface with gear and limited to a smallest cone diameter by a hub surface. For fixing the synchronizer ring in the installed state in a cylindrical cavity of a synchronous ring hub, a rotation lock is provided, which is integrally connected to the annular body and extends in a direction away from the gear surface of the annular body. According to the invention, a guide element is provided for guiding the mounting surface in the cylindrical cavity on the anti-twist device.

It is essential for the invention that a guide element is provided on the anti-twist device for supporting or centering and guiding the installation surface on an inner surface of the cylindrical cavity of the synchronizing ring hub.

Characterized in that the guide elements are provided on the anti-rotation, a synchronizer ring according to the invention is at the same time outstandingly secured against rotation relative to the Synchronringnabe by Verdrehsicherungen, and is simultaneously guided and centered reliably, in particular with respect to the radial direction in the cylindrical cavity in the synchronizer ring. The conical friction surface is in no way affected by the guide elements, as the Guide elements are provided away from the conical friction surface on the anti-rotation.

That is, a synchronizer ring according to the present invention, due to its conical outer shape, which cooperates with a cylindrical inner contact surface in the cylindrical cavity of the synchronizer ring hub, no longer tends, like the conical synchronizer rings known from the prior art, to uncontrolled movements, e.g. to small radial deflections or tilting movements, e.g. can express in unpleasant vibrations. At the same time the friction surface or the annular body is impaired in any way. This means that the ring body retains its full stability and the entire conical friction surface is available for the synchronization process. Thus, the reliability and accuracy of the synchronization process by using a synchronizer ring according to the invention is significantly positively influenced, which can be a reduction in the switching times, reduces the wear on the friction surface and the entire synchronizer ring as such and thus contributes to longer repair and maintenance intervals, quite apart of the fact that the switching and driving comfort of a motor vehicle is significantly increased by the excellent guidance of the synchronizing ring according to the invention in the cavity of the synchronizing ring hub. These positive effects have the stronger effect, the more power or torque must be switched by a corresponding gear.

In practice, the guide element is usually an integral part of the rotation and is together with this during the forming process, for. produced from a steel sheet.

In a specific embodiment, the guide element extends from the anti-rotation in the circumferential direction, preferably in two opposite directions, so that a relatively wider saddle-shaped area is formed, which is the safe Guiding the synchronizer ring in the cylindrical cavity of the synchronous ring hub reliably guaranteed.

It is also possible that the guide element, starting from the rotation in the circumferential direction asymmetrically extends only in a circumferential direction, in particular three anti-rotation, each with a guide element are provided. That is, it is also possible that the guide element is provided in the form of a centering tab only on one side of the rotation, which reduces the design effort and the cost of materials accordingly.

In another specific embodiment, the guide element extends in a region between the anti-rotation and the outer mounting surface in the direction of the circumferential direction.

It is also possible that the guide element extends on a side facing away from the gear surface of the rotation along the rotation in the circumferential direction, or, for example, that the rotation is connected to the guide member via a bridge and is provided on a retaining tab.

Which particular embodiment is selected in the specific application can depend, for example, on the mechanical load in the operating state or on geometric specifications by the remaining part of a transmission, such as, for example, the specific geometric design of the other parts of the transmission or other specific boundary conditions be.

It is essential that the guide elements are provided directly to the anti-rotation and are not formed on the friction surface or on the ring body and not consuming as separate tabs.

In a specific embodiment, the gear surface is through a recess, in particular by one, or two, or three, or more than interrupted three recesses, and / or the rotation is connected in the recess with the annular body.

Here are preferred, but not necessary, as many anti-rotation as recesses provided in the gear surface. In a particularly important for practice embodiment exactly three anti-rotation are provided, which guarantee a minimum of rotation and guidance by the guide elements with minimal design effort.

In particular, the rotation can be formed as a securing tab, which extends on the side facing away from the synchronizer ring axis of the ring body substantially rectified to the mounting surface.

In a very specific embodiment, the securing tab may be a securing tab with a pocket-shaped recess, whereby in an individual case an improved anchoring of the synchronizing ring in the synchronizing ring hub can be achieved.

Preferably, a wear-reducing and / or a friction-optimized friction means, in particular a friction coating, in particular a molybdenum coating and / or a friction lining, in particular a carbon friction lining and / or another friction means are provided on or on the friction surface.

It is understood that in certain cases no friction lining can be provided on the friction surface, e.g. then, but not only, when the sync ring is part of a multi-cone sync.

Constructively, the synchronizer ring is made of a thermoformable sheet metal formed part and / or made of a steel, preferably made of C55, C80 or C80M steel, in particular C35 or C45 steel.

The invention further relates to a transmission for a vehicle, in particular for a passenger car, a van or a Truck with a synchronizer ring according to one of the preceding claims.

Fig. 1

ein aus dem Stand der Technik bekannter Synchronring im Schnitt;

Fig. 2

eine Seitenansicht des Synchronrings gemäss Fig. 1 im Einbauzustand;

Fig. 3

ein erstes Ausführungsbeispiel eines erfindungsgemässen Synchronrings;

Fig. 4

der Synchronring der Fig. 3 im Einbauzustand;

Fig. 5

ein zweites Ausführungsbeispiel eines erfindungsgemässen Synchronrings;

Fig. 6

ein drittes Ausführungsbeispiel eines erfindungsgemässen Synchronrings;

Fig. 7

ein viertes Ausführungsbeispiel eines erfindungsgemässen Synchronrings;

In the following the invention will be explained in more detail with reference to the schematic drawing. Show it:

Fig. 1

a known from the prior art synchronizer ring in section;

Fig. 2

a side view of the synchronizer ring according Fig. 1 in the installed state;

Fig. 3

a first embodiment of an inventive synchronizer ring;

Fig. 4

the synchronizer ring of Fig. 3 in the installed state;

Fig. 5

A second embodiment of an inventive synchronizer ring;

Fig. 6

A third embodiment of an inventive synchronizer ring;

Fig. 7

A fourth embodiment of an inventive synchronizer ring;

The Fig. 1 and Fig. 2 , which show a known from the prior art synchronizer ring, have already been described in detail at the beginning, so that these figures need not be discussed below.

Fig. 3 shows in a schematic representation in section an embodiment of an inventive synchronizer ring, which is hereinafter referred to collectively with the reference numeral 1. Here, like reference numerals in the various figures indicate technically equivalent features or relate to features with technically equivalent function.

The synchronizer ring 1 of Fig. 3 includes a conical annular body 3 with an inner friction surface 4 with carbon friction lining 41 and an outer mounting surface 5, which limit the annular body 3 in a radial circumferential direction in a conventional manner in each case. The outer mounting surface 5 and the inner friction surface 4 extend substantially parallel to each other at a predeterminable friction angle, which in Fig. 1 is not conical about an axial synchronizer ring axis 6, which in Fig. 3 is shown in a non-scale distance to the friction surface 4.

Here, the annular body 3 is limited in the axial direction at a maximum cone diameter by a substantially perpendicular to the synchronizer ring axis 6 extending gear surface 7 with gear 71, and limited to a smallest cone diameter by a hub surface 8, in the perspective view of Fig. 3 not visible. For fixing the synchronizer ring 1 in a cylindrical cavity 9 of a synchronizer ring hub 10, which in Fig. 3 is also not shown, a rotation 11 is provided, which is integrally connected to the ring body 3 and extends from the gear surface 7 of the ring body 3 in the direction of the hub surface 8, a construction as it is already known in principle from the prior art , It is the Anti-rotation 11 according Fig. 3 For example, in the manufacture of the synchronizer ring 1 by bending over a portion of the ring body 3 initially still radially outwardly in the direction of the mounting surface 5 has been formed.

That is, the rotation 11 extends on the side facing away from the synchronizer ring axis 6 side of the annular body 3 is substantially rectified to the mounting surface. 5

As will be explained in more detail later with reference to the following figures, the anti-rotation 11 is designed and arranged with respect to the mounting surface, that the rotation 11 in the installed state in a corresponding recess 101 of the synchronizer hub 10 is anchored.

According to the invention for guiding the mounting surface 5 on an inner surface 91 of the cylindrical cavity 9 of the synchronizer ring hub 10, which as mentioned in Fig. 3 not shown, because Fig. 3 does not show the synchronizer ring 1 in the installed state, provided on the anti-rotation 11, a guide member 12. The guide member 12 is an integral part of the rotation 11 and extends from the rotation 11 in the circumferential direction U in two opposite directions.

In the installed state of the synchronizer ring 1, the guide element 12 according to the invention centers and guides the synchronizer ring 1 reliably and reliably in the cylindrical cavity 9 provided in the synchronizer ring hub 10 for receiving the mounting surface 5.

In Fig. 4 is a side view of a synchronizer ring 1 according Fig. 1 shown schematically in the installed state. In the Fig. 4 shown sectional plane is perpendicular to the synchronizer ring axis 6, which in turn is shown a non-scale true spacing.

The conical annular body 3 with its inner friction surface 4, which has a carbon friction lining 41 in the present example, and the outer mounting surface 5, extend conically at the friction angle and essentially parallel to one another about the axial synchronizer ring axis 6 of the synchronizer ring 1.

The synchronizer ring 1 is centered by the inventive guide elements 12 which are provided on the anti-rotation 11, with the mounting surface 5 in the cavity 9 of the synchronizer ring hub 10.

In the Fig. 4 For reasons of clarity not shown gear surface 7 with gear 71 is located in a conventional manner outside the synchronizer hub 10, so that the gear 71 with another, in Fig. 4 not shown gear of a switchable change-speed transmission also not shown in rotationally fixed engagement can occur.

In the Fig. 5 to Fig. 7 three further specific embodiments of the invention synchronizer rings are shown schematically, each with each other or from the specific embodiment of Fig. 3 differ only by the special arrangement of the guide member 12 on the anti-rotation 11.

In the specific example of Fig. 5 extends the guide member 12 on a side facing away from the gear surface 7 of the rotation 11 along the rotation 11 in the circumferential direction U. There is a larger area for supporting the synchronizer ring 1 in the synchronizer ring hub 10 available, as for example in the synchronizer rings 1 of Fig. 3 . 6 and 7 , A synchronizer ring 1 according Fig. 5 Consequently, one will therefore always choose, when due to the special circumstances, a particularly large support surface for supporting the synchronizer ring 1 in the synchronizer ring hub 10 is required.

In the embodiment according to Fig. 6 the guide element 12 extends in a region between the anti-rotation 11 and the outer mounting surface 5 in the circumferential direction U, that is arranged between the anti-rotation 11 and the mounting surface 12. The example of Fig. 6 is thus a variant which is particularly space-saving in the axial direction towards the synchronizing ring hub 10.

Based on Fig. 7 a very particular variant of an inventive synchronizer ring 1 is shown, in which the anti-rotation 11 is provided with the guide member 12 via a bridge 14 on a retaining tab 15. This type of construction gives the guide element 12 a certain elasticity under pressure load in the radial direction, so that the synchronizer ring 1 is guided very smoothly and safely, for example, under loads which vary in time in the radial direction.

It is understood that all embodiments explicitly discussed in this application are to be understood as exemplary of the invention and in particular also all suitable combinations that can be advantageously used for specific applications, or all developments close to the skilled person are covered by the invention.

Claims (15)

Synchronizer ring for a synchronizer (2) of a change-speed gearbox comprising a conical ring body (3) with an inner friction surface (4) and an outer mounting surface (5), the annular body (3) in a radial circumferential direction (U) perpendicular to a axial synchronizer ring axis (6) extends, in each case limit, and extend at a predefinable friction angle conically around the axial synchronizer ring axis (6) of the synchronizer ring, wherein the annular body (3) in the axial direction at a maximum cone diameter by a substantially perpendicular to the synchronizer ring axis ( 6) extending gear surface (7) with gear (71) is limited, and at a smallest cone diameter by a hub surface (8) is limited, and for fixing the synchronizer ring in the installed state in a cylindrical cavity (9) of a synchronizer ring hub (10) an anti-rotation (11) is provided, which is integrally connected to the annular body (3) and in a direction v on the gear surface (7) of the annular body (3) extends away, characterized in that for guiding the mounting surface (5) in the cylindrical cavity (9) on the rotation (11), a guide element (12) is provided. Synchronizer ring according to claim 1, wherein the guide element (12) is an integral part of the anti-rotation device (11). Synchronizer ring according to one of claims 1 or 2, wherein the guide element (12), starting from the anti-rotation device (11) in the circumferential direction (U) extends, preferably in two opposite directions. Synchronizer ring according to one of the preceding claims, wherein the guide element (12), starting from the rotation (11) in the circumferential direction (U) extends, preferably only in a circumferential direction (U), in particular three anti-rotation (11), each with a guide element (12) is provided. Synchronizer ring according to one of the preceding claims, wherein the guide element (12) in a region between the anti-rotation (11) and the outer mounting surface (5) in the circumferential direction (U). Synchronizer ring according to one of the preceding claims, wherein the guide element (12) on one of the gear surface (7) facing away from the rotation (11) along the rotation (11) in the circumferential direction (U). Synchronizer ring according to one of the preceding claims, wherein the anti-rotation device (11) with the guide element (12) via a bridge (14) on a retaining tab (15) is provided. Synchronizer ring according to one of the preceding claims, wherein the gear surface (7) by a recess (13), in particular by one, or two, or three, or more than three recesses (13) is interrupted, and / or the anti-rotation (11) in the recess (13) is connected to the annular body (3). Synchronizer ring according to one of the preceding claims, wherein as many anti-rotation devices (11) as recesses (13) in the gear surface (7), in particular exactly three anti-rotation devices (11) are provided. Synchronizer ring according to one of the preceding claims, wherein the anti-rotation (11) is designed as a securing tab (111) extending on the synchronizer ring axis (6) facing away from the ring body (3) substantially rectified to the mounting surface (5). Synchronizer ring according to one of the preceding claims, wherein the securing tab (111) is a securing tab (1110) with a pocket-shaped recess. Synchronizer ring according to one of the preceding claims, wherein no friction lining (41) on the friction surface (4) is provided and the Synchronous ring is in particular a part of a multi-cone synchronization. Synchronizer ring according to one of the preceding claims, wherein on the friction surface (4) a wear-reducing and / or friction-optimized friction means (41), in particular a friction coating (41), in particular a molybdenum coating (41) and / or a friction lining (41), in particular, a carbon friction lining (41) and / or another friction means (41) is provided. Synchronizer ring according to one of the preceding claims, wherein the synchronizer ring is a sheet metal formed from a deep-drawing sheet metal part and / or made of a steel, preferably made of C55, C80 or C80M steel, in particular C35 or C45 steel. Gear change transmission for a vehicle, in particular for a passenger car, a van or a truck with a synchronizer ring (1) according to one of the preceding claims.

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